This project covers studies examining behavioral and biological response of depressed patients to pharmacologic agents. Three separate studies are involved. The first is an extension of a previous study examining clinical response of depressed subjects to amphetamine; we are now preparing to look at biological response of these patients. The second study involves mood, noradrenergic, and neuroendocrine changes in manic and depressed subjects in response to intravenous clonidine infusions. The third study looks at changes in mood, memory, sleep patterns, and electrophysiology in depressed patients in response to ACTH and its centrally acting analog, ACTH 4-9.